Key mechanism for mechanical calculators



Aug. 4, 1970" T. ARVAY kEY MECHANISM FOR MECHANICAL CALCULATORS 4Sheets-Sheet 1 Filed Dec. 19, 1968 Fig. I

1970 T.' ARVAY KEY MECHANISM FOR MECHANICAL CALCULATORS 4 Sheets-SheetFiled Dec. 19, 1968 Aug. 4, 1970 ARVAY 3,522,418

KEY MECHANISM FOR MECHANICAL CALCULATORS Filed Dec. 19, 1968 U U 4Sheets-Sheet 3 A f, m ,I 77 u l] Aug. 4, 1970 T. ARVAY KEY MECHANISM FORMECHANICAL CALCULATORS 4 Sheets-Sheet 4 Filed Dec. '19, 1968 UnitedStates Patent 3,522,418 KEY MECHANISM FOR MECHANICAL CALCULATORS TiborArvai, Villevaude, France, assignor to Sperry Rand Corporation, Norwalk,Conn., a corporation of Delaware Filed Dec. 19, 1968, Ser. No. 785,246Claims priority, application France, Dec. 20, 1967, 133,206 Int. Cl.G06c 21/04 U.S. Cl. 235-145 Claims ABSTRACT OF THE DISCLOSURE Acalculating machine of the moving carriage type has control meansoperated by a key which is movable selectively to either side of acentral, neutral position. This movement is transmitted to a leverpivoted at one end, the movement of the key causing longitudinalmovement of the lever in the selected direction. The other end of thelever carries a ramp which serves to position a cam mechanism whichcontrols the operation of the calculating machine. In addition to beinglongitudinally movable by the operating key, the lever is laterallydisplaced about its pivot by the carriage when the latter is in itsinoperative position. The control ramp therefore has four possiblepositions corresponding to four different operations of the calculatingmachine.

The present invention relates to mechanical calculators of the ten-keytype and it concerns more particularly a control mechanism which isindispensable for carrying out the various arithmetical operations thatare desired. Such-mechanisms are frequently complex both as regardstheir construction and as regards their operation. The mechanism formingthe subject-matter of the present application produces a very greatsimplification in the known mechanisms on the two planes in question.The calculator for which the present mechanism is specially designed isa two-operation calculator, that is to say a calculator enablingadditions and subtractions to be effected. Of course, such a calculatorcan enable totals and subtotals to be taken. It is obvious,nevertheless, that the same mechanism could be used on a four-operationcalculator with the same results. Obviously a three-operation orfour-operation calculator requires supplementary mechanisms for enablingmultiplications and divisions to be effected.

The calculator according to the invention may be of the type thatincludes a pin carriage for receiving and storing temporarily the dataintroduced from a keyboard. The depression of a numeral key istranslated into the setting of a pin in the carriage and an escapemovement of the carriage to the left by one column. The progressiveentries of the data continue to set the pins in the successive columnsand to cause the escape of the carriage until such time as the latter isfully filled and has reached the limit of its travel.

On the depression of an actuating key, the data introduced into the pincarriage are read and said carriage is cleared and then returns to itsinitial position in which it is ready to receive the data to follow.

The present invention takes into account the fact that, for operationsentailing an addition or a subtraction, the data will have always beenintroduced and, consequently, the carriage will have always performed anescape to the left of the value of at least one column. When it isdesired to take a total or a subtotal, the carriage will always becleared and will return to its initial position. Due to the presence ofan actuating key which has two possible actuating positions and bytaking account of the position of the pin carriage, it is alwayspossible to effect additions and subtractions and to take totals andsubtotals with the aid of a single actuating key.

The description which follows with reference to the accompanyingdrawings and given by way of non-limitative example will make it clearlyunderstood how the invention can be carried into effect, the detailsappearing both from the drawing and from the text forming, of course,part of said invention.

FIG. 1 is a plan view of a calculator showing the actuating key as wellas the numeral keys and also in part the mechanism associated with theactuating key for obtaining the desired results;

FIG. 2 is a section in side view of the calculator and shows inparticular the pin carriage;

FIG. 3 is a plan view of the lever mechanism which is operated jointlyby the actuating key and by the pin carriage;

FIG. 4 is a front view of the mechanism actuated from the mechanism ofthe actuating key according to FIG. 3.

The calculator includes a keyboard 22 equipped with keys 25 serving toenter the digits from 0 to 9.

In each of the keys 25 corresponding to the digits from 0 to 8 inclusivethere is fixed a cable sliding in a sheath 23. The free end of thiscable bears on a pin 16 and shifts the latter when the corresponding keyis actuated.

The depression of each of the keys 25 causes the depression of aT-element 30 which, through the medium of a cable sliding in a sheath23a, pushes in the pin 16a of the ninth position. Since the pin 16abears against a fixed part 31, a carriage 20 biased by a spring 21 movesto the left until the pin 16a of the following column bears against thepart 31, this system serving to shift the carriage 20 after the entry ofeach digit.

The calculating mechanism proper is composed of a sector 1 movable abouta spindle 13 and adapted to bear by means of its end In on one of thepins 16 which has been previously pushed in from the keyboard. Thesector 1, which carries a toothing 1e, meshes permanently with a rack 2furnished with raisetd numerals 2a from 0 to 9 and thus presenting thedigit to be printed on the impact of a hammer 3.

The sector 1 also carries a toothing 1b which can mesh with an addingwheel 4 mounted rotatably on a spindle 4b and transmit to said addingwheel the angular value corresponding to that read on the entry pin ofthe corresponding decimal column. Conversely, in the event of it beingdesired to effect a total or partial total, this same toothing 1b canread the angler value or the number of teeth which has been introducedinto the corresponding decimal adding wheel. To this end, a Wider tooth4a, called the tens carry tooth and corresponding to the zero point,serves as a stop against a reading stirrup 5. Between the passage of thetooth corresponding to the digit nine and the passage of the toothcorresponding to the digit zero, for addition, the carry tooth 4a raisesa carry signal pawl or catch 6 which is articulated at 611. Theprojection 6b carried by this pawl raises in turn a lever 7 which isflexible at 7a and this releases the carry sector 8 which is shifted bythe value of one tooth under the influence of the spring 9. The sameeffect occurs in subtraction between the passage of the toothcorresponding to the digit zero and the passage of the toothcorresponding to the digit nine.

So that this carry may be registered as an addition or a deduction inthe higher decimal column, the carry sector 8 is elbowedat 8a (FIG. 1)so as to mesh with the adding Wheel of the following decimal column.

The blades of the spring 9 are riveted to a spindle 10 which is given anangular reciprocating movement programmed by a cam 11 and synchronisedwith the clutch of the adder on the calculating or carry sectors, theclutch 3 of the adder being itself programmed by a cam 12 (FIG. 1).

The driving of the sectors 1 about the spindle 13 is obtained by meansof spring blades 14 riveted to a stirrup 15 pivoting at 15a and bearingon a stud 10 carried by the sector 1.

The printing lock 18 rocks when the sector 1 is shifted by an angularvalue corresponding to at least one tooth. This locking element allowsthe striking of the hammer 3 when the recess 17a of the cam 17 ispresented in front of the lug 3a, the hammer 3 being urged by a springblade 72 fast with the member 7. An impression device 50 enables thedigits carried by the bars to be written down.

The arrangement which has just been described is of a conventional typeto which is fitted the control mechanism according to the invention,which comprises a key controlling the entry of the various operations.

This actuating key comprises a single pivoting bar 26 (FIG. 1) fromwhich depends a lever arm (not shown). When the upper portion of the bar26 of the type shown in FIG. 1 is depressed, the lower end of theassociated lever arm is shifted towards the rear. By depressing thelower portion of the bar 26, the lower end of the lever arm movesforward. The lower end of the lever engages in a slot 101 formed in acentrally articulated lever 102 with which there are associated a springmechanism 103 for placing the lever 102 in the neutral position, alocking mechanism 104 and another mechanism 106, which is an engagingmechanism enabling a rotary clutch to be made to operate and action tobe exerted on an electric switch so as to start a motor. This lastmechanism does not form part of the invention and will therefore not bedescribed.

Depending on the particular end of the bar 26 which has been depressed,the lever 102 pivots clockwise or anticlockwise. A lever 60 isarticulated to a pivot 107 and this lever can be seen more clearly inFIG. 3. Depending on the end of the bar 26 which has been depressed,this lever 60 is either driven forward or retracted. By reason of itsarticulation at 107, it will be seen that the lever 60 can also swingclockwise or anticlockwise about this articulation. When the pincarriage is in its inoperative position, an extension 20a of thecarriage 20 bears against the lever 60 and tends to cause it to pivotclockwise. Once the data have been introduced into the carriage, theextension 20a is retracted and the lever 60 can move freelyanticlockwise and is urged in this direction by a return spring 81 whichacts through the medium of an intermediate mechanism describedhereinafter.

It is therefore obvious that the lever 60 has two degrees of freedom; infact, it can move rearward or forward and it can pivot from one side tothe other.

At the upper end of the lever 60 a ramp surface 60a (FIG. 3) is formed.This ramp surface co-operates with a slot 800 in a cam mechanism 80which is shown more clearly in FIG. 4. Such a mechanism 80 iscontinuously urged to the left under the action of the return spring 81.A fork element 80a is fixed to the cam mechanism 80 and forms part ofthe latter, as shown in FIG. 3. This fork element comes into engagementwith a cam follower 61 (see FIG. 1), the latter being able both to slideand to turn on a supporting shaft 61a. One end of the cam follower 61comes constantly into engagement with a hoop or cradle 190, while itsother end co-operates with a multiple-track cam 12. The cradle 19ccontrolling the adder, this or that desired action of the mechanism ofthe calculator can be produced according to the particular track onwhich the cam follower 61 acts. It will be suflicient to observe thatthe number of tracks on the cam is four and that they correspondrespectively to the operations of addition, subtraction, taking of atotal and taking of a sub-total by the machine.

Consequently, to effect an addition, the upper end of the bar 26 isdepressed after the necessary data have been introduced. The pincarriage will not be in its inoperative position and the lever 60 willbe in the retracted position which is shown in FIGS. 1 and 3.Consequently, the ramp surface 60a will be disengaged from the slot cand, under the action of the return spring 81, the cam mechanism 80 willbe in the extreme left-hand position (see FIGS. 1, 3 and 4). As aresult, the cam follower 61 (FIG. 1) is disposed on the left-hand trackof the cam 12, which track corresponds to the addition operations.

If it is desired to effect a subtraction, once the data have beenintroduced the lower end of the bar 26 is depressed as seen in FIG. 1.This action drives the lever 60 forward, so that the engagement of thecam surface 60a forces the cam 80 to move to the right by one step inopposition to the action of the spring 81, as a result of which the camfollower 61 will be transferred to the following track of the cam 12,this track being located immediately to the right. It will be understoodthat as before the pin carriage will not be in engagement with the lever60.

To take a total, the upper end of the bar 26 is again dopressed. Underthese conditions, however, the carriage is cleared and is located in itsextreme right-hand position, in which it bears against the lever 60 andpushes it against the stop 60b. However, owing to the fact that thelever 60 is shifted as a result of the operation of the bar 26, the rampsurface 60a is released from the slot 800. Consequently, the positionoccupied by the cam 80 is one step more to the left with respect to itsextreme right-hand position. In this case, the cam follower 61 isdisposed on that track of the cam 12 which corresponds to the taking ofthe total.

Finally, to take a sub-total, the pin carriage bears against the lever60, pushing it clockwise, and at the same time the depression of thelower portion of the bar 26 brings the ramp surface 60a into contactwith the slot 800. The cam 80 is then in its extreme right-hand positionand the corresponding position of the cam follower 61 is on the extremetrack of the cam 12 and the mecha nism for taking sub-totals is therebycorrectly actuated.

It is obvious that the constructional form described is only an exampleand that it would be possible to modify it, in particular bysubstituting equivalent technical means, without departing from thescope of the invention.

I claim:

1. Control mechanism for a calculating machine of the kind describedcomprising a lever articulated about an axis, a pivotally mountedoperating bar for selectively moving said lever about said axis, saidlever carrying an inclined ramp, said inclined ramp controlling theshifting of a cam follower cooperating with a multiple-track cam so asto position said follower in register with the selected track of saidmultiple-track cam.

2. Mechanism according to claim 1, wherein said lever is articulated toa second lever adapted to pivot about a fixed axis and the second leveris connected to the bar.

3. Mechanism according to claim 2, wherein said second lever includes aslot in which a lever-arm secured to the pivoting bar is engaged.

4. Mechanism according to claim 2, comprising resilient means for urgingsaid second lever to the neutral position.

5. Mechanism according to claim 1, wherein the articulated lever isresiliently biased in one direction and a part on the carriage of thecalculating machine is adapted to act on asid lever in the directionopposite to said one direction.

References Cited UNITED STATES PATENTS 2,821,341 1/1958 Earnhardt 235-603,030,018- 4/1962 Ellerbeck 23s-14s 3,315,889 4/1967 Thevis 235- STEPHENJ TOMSKY, Primary Examiner U.S. c1. X.R.

